Giling Basah, only in Indonesia
Giling Basah or "Wet Hulled" is a process used by Indonesian coffee processors and is specific to this region. Wet hulled coffees emphasizes body over brightness, and savory over sweetness.
Why only Indonesia?
Indonesia's tropical climate is mostly hot with up to 90% humidity levels. Dry season occurs between May - October, leaving November - April for the rain season. With these types of high moisture environments specific to this region, it is extremely difficult to dry coffee consistently for extended periods.
Wet Hulled Process
While you can find natural, washed, honey process coffees in Indonesia, wet hulled is the common practice among small farm holders. Hopefully the steps below will give you a better understanding of what the term wet hulled refers to.
- Sorting - Farmers collects coffee beans and sorted by size and density using water.
- Depulping - Machines removes the outer skin and pulp of the coffee cherries leaving behind a layer of mucilage (fruit layer beneath the skin).
- Fermentation - To breakdown the mucilage, the beans are soaked in water overnight (known as fermentation), which makes it easier to wash off the mucilage to get to the parchment (thin layer protecting the seed).
- Washing - After overnight fermentation, coffee beans are washed the following morning. This process also allows to sort beans by density.
- 1st Drying - At this stage of the drying process, the seeds will have a moisture content of about 50%. In this stage, parchment will be dried on patios or raised beds until the seeds reach 30% moisture content. This stage of drying can take anywhere from an hour to a full day depending on humidity and cloud conditions.
- Wet Hulling - Machines remove the semi dry parchment layer from the seeds before they are fully dry. A wet huller works on the same principle as other hulling machines, but designed to operate in a much wetter environment to draw off water in addition to parchment.
- 2nd Drying - Green beans are dried for the 2nd time on patios or raised beds until it reaches 12% moisture content.
In other growing regions of the world, the parchment is left on the seed with about 10-12% moisture until it is ready to export. Due to the moisture and cloudy conditions, it is difficult to dry the seeds still within its parchment. Removing that layer while the seed is still wet allows the seed to dry efficiently. As a result, your coffee can go from picking to shipping in a month; whereas, other coffee regions takes several months to dry, bag, rest and hull.